JP2014155044A - Image reading apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reading apparatus which, when a sheet is inserted between a peripheral surface of a roller and a reading surface of a reading part, can suppress that a leading end of the sheet is caught by a reading part.SOLUTION: An image reading apparatus 1 includes a first extension part 151 and a second extension part 153. The first extension part 151 is extended from a front plate 118 of a reading part 83 to the front side. The second extension part 153 is extended from a fifth wall surface 47 of a lower chute 41 to the rear side and located on the upper side of the first extension part 151. When force is applied from a roller 82 to a reading surface 122, the first extension part 151 is abutted on the second extension part from the lower side and the force is received by the second extension part 153. Consequently, rotation of the reading part 83 due to the force applied from the roller 82 to the reading surface 122 can be suppressed, and when a sheet is inserted between the peripheral surface of the roller 82 and the reading surface 122 of the reading part 83, a situation where the leading end of the sheet is caught by the reading part 83 can be suppressed.

Description

  The present invention relates to an image reading apparatus.

  In the image reading apparatus disclosed in Patent Document 1, a reading unit and a roller are provided. The roller is disposed above the reading surface of the reading unit. The sheet is conveyed between the peripheral surface of the roller and the reading surface by the rotation of the roller. Then, when the sheet passes on the reading surface, the image on the reading surface side of the sheet is read by the reading unit.

  The contact position between the peripheral surface of the roller and the reading surface is biased to the downstream side in the sheet conveyance direction in the reading unit. A pressing spring is provided below the reading unit. The pressing spring presses a portion of the reading unit that is biased to the downstream side in the sheet conveyance direction toward the roller. By this pressing, the reading surface is brought into close contact with the sheet conveyed between the peripheral surface of the roller and the reading surface. Therefore, the image of the sheet on the reading surface can be satisfactorily read by the reading unit.

JP-A-8-259032

  However, when the roller rotates, a force in a direction to push down the contact position between the peripheral surface of the roller and the reading surface is applied from the roller to the reading unit. By this input, the pressing spring is compressed. Accordingly, the reading unit rotates so that the downstream portion in the transport direction is lowered and the upstream portion in the transport direction is raised. As a result, when the sheet is inserted between the peripheral surface of the roller and the reading surface, the leading edge of the sheet may be caught by the upstream portion of the reading unit in the transport direction.

  An object of the present invention is to provide an image reading apparatus capable of suppressing the leading edge of the sheet from being caught by the reading unit when the sheet is inserted between the peripheral surface of the roller and the reading surface of the reading unit. is there.

  In order to achieve the above object, an image reading apparatus according to the present invention includes a reading unit having a reading surface and configured to read an image of a sheet positioned on the reading surface, and a part of the peripheral surface. A roller that contacts the reading surface at a contact position biased to the downstream side in the sheet conveying direction in the reading unit; a first extending portion that is provided in the reading unit and extends upstream in the conveying direction; and the reading surface And a second extending portion that is located on the roller side with respect to the first extending portion and extends downstream in the conveying direction.

  According to this configuration, a part of the peripheral surface of the roller is in contact with a contact position that is biased to the downstream side in the sheet conveyance direction on the reading surface. Therefore, when the roller rotates, a force is applied from the roller to the reading surface in a direction in which a portion of the reading unit on the downstream side in the transport direction moves to the opposite side of the roller. The first extending portion extends from the reading portion to the upstream side in the transport direction. The second extension is located on the roller side with respect to the first extension. When a force is applied from the roller to the reading surface, the first extending portion comes into contact with the second extending portion from the side opposite to the roller side, whereby the force is received by the second extending portion. Thereby, rotation of the reading unit due to the force applied from the roller to the reading surface can be suppressed. As a result, when the sheet is inserted between the peripheral surface of the roller and the reading surface of the reading unit, the leading edge of the sheet can be suppressed from being caught by the reading unit.

  The first extending portion may be configured by a protrusion that is located on the opposite side of the reading surface from the roller side in the orthogonal direction and protrudes from the upstream end surface in the conveying direction of the reading unit to the upstream side in the conveying direction. The second extending portion is located on the opposite side of the reading surface from the roller side in the orthogonal direction, and protrudes downstream in the transport direction from a wall portion located upstream of the reading portion of the housing that houses the reading portion. It can be composed of the protrusions.

  The image reading apparatus may include an urging unit configured to abut on a portion of the reading unit opposite to the reading surface and to urge the reading unit toward the roller.

  According to this configuration, when the reading unit is biased toward the roller, the reading surface can be brought into close contact with the sheet conveyed between the peripheral surface of the roller and the reading surface. Therefore, the image of the sheet on the reading surface can be satisfactorily read by the reading unit.

  The contact position of the reading unit with the urging unit is preferably the same position as the contact position in the transport direction.

  Accordingly, when a force is applied from the roller to the reading surface as the roller rotates, a part of the force can be received by the urging unit. As a result, the rotation of the reading unit due to the force applied from the roller to the reading surface can be further suppressed.

  The image reading apparatus includes a protruding portion provided in the reading portion, and the protruding portion is positioned on the roller side with respect to the first extending portion and the second extending portion in the orthogonal direction, and is located on the upstream end surface in the conveying direction of the reading portion. In contrast, it is preferable that the protrusion protrudes upstream in the transport direction, and the protrusion has an inclined surface that is inclined so as to approach the reading surface toward the downstream in the transport direction.

  According to this configuration, the inclined surface of the protrusion can be used as a guide when the sheet is disposed on the reading surface. Thereby, the sheet can be smoothly arranged on the reading surface.

  Further, in the direction orthogonal to the reading surface, the inclined surface is inclined so as to be farther from the reading surface toward the upstream side in the transport direction. Therefore, when a chute that supports the sheet from the side opposite to the roller side is provided on the upstream side in the conveyance direction of the reading unit, the chute can be brought close to the reading surface in a direction orthogonal to the reading surface. Thereby, it is possible to reduce the size of the image reading apparatus in the direction orthogonal to the reading surface.

  The reading unit may include an extending part extending from the first extending part to the roller side in the orthogonal direction, and the housings are respectively positioned on one side and the other side in the rotation axis direction of the roller with respect to the extending part. And you may provide the two walls extended on the opposite side to the roller side in the orthogonal direction.

  Thereby, it can suppress that a reading part moves to a rotating shaft direction.

  According to the present invention, when a force is applied from the roller to the reading surface along with the rotation of the roller, the first extending portion comes into contact with the second extending portion from the side opposite to the roller side. The rotation of the reading unit can be suppressed. As a result, when the sheet is inserted between the peripheral surface of the roller and the reading surface of the reading unit, the leading edge of the sheet can be suppressed from being caught by the reading unit.

1 is a plan view of an image reading apparatus 1 according to an embodiment of the present invention. 2 is a front view of the image reading apparatus 1. FIG. 2 is a right side view of the image reading apparatus 1. FIG. FIG. 2 is a cross-sectional view of the image reading apparatus 1 taken along a cutting plane line AA shown in FIG. 1. FIG. 3 is a cross-sectional view of the image reading apparatus 1 taken along a cutting plane line BB shown in FIG. 2. FIG. 3 is a cross-sectional view of the image reading apparatus 1 taken along a cutting plane line CC shown in FIG. 2. FIG. 3 is a cross-sectional view of the image reading apparatus 1 taken along a cutting plane line DD shown in FIG. 2. 3 is a perspective view of the lower chute 41 of the image reading apparatus 1 as viewed from the upper right front side. FIG. FIG. 3 is a perspective view of the lower chute 41 as viewed from the upper right rear side. 2 is a plan view of the image reading apparatus 1 in a state where a top cover 4 of the image reading apparatus 1 is removed. FIG. 2 is a front view of the image reading apparatus 1 with a top cover 4 removed. FIG. 4 is a perspective view of the reading unit 83 of the image reading apparatus 1 as viewed from the upper right front side. FIG. 4 is a plan view of a reading unit 83. FIG. FIG. 2 is a cross-sectional view of the image reading apparatus 1 and shows a state where a roller 82 is not rotating. FIG. 2 is a cross-sectional view of the image reading apparatus 1 and shows a state where a roller 82 is rotating. It is explanatory drawing for demonstrating a 1st modification, and shows the state which the roller 82 is not rotating. It is explanatory drawing for demonstrating a 1st modification, and shows the state which the roller 82 is rotating. It is explanatory drawing for demonstrating a 2nd modification, and the state which the roller 82 is not rotating is shown. It is explanatory drawing for demonstrating a 2nd modification, and shows the state which the roller 82 is rotating.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Case>

  As shown in FIGS. 1, 2, and 3, the image reading apparatus 1 includes a housing 2. The housing 2 is divided into a bottom cover 3 and a top cover 4.

  In the following description, the top cover 4 side with respect to the bottom cover 3 is the upper side, and the side on which the introduction port 71 described later is formed with respect to the center of the image reading apparatus 1 in plan view is the front side. Define the front and back directions. And in each figure after FIG. 1, a direction is displayed with an arrow.

  As shown in FIG. 2, the bottom cover 3 includes a bottom surface portion 5 and a right side surface portion 6.

  The bottom surface portion 5 extends in the left-right direction.

  The right side surface portion 6 extends upward from the right edge of the bottom surface portion 5. As shown in FIG. 3, an insertion port 7 is formed in the right side surface portion 6. The insertion port 7 penetrates the right side surface part 6 in the left-right direction. The insertion port 7 exposes the communication connector 8 disposed on the left side of the right side surface portion 6. A terminal provided at one end of a communication cable (not shown) is inserted into the communication connector 8 through the insertion port 7.

  As shown in FIGS. 2, 3, and 4, the top cover 4 overlaps the bottom cover 3 from above. As shown in FIGS. 4, 5, 6, and 7, the top cover 4 includes a left side surface portion 11, a right side surface portion 12, an upper surface portion 13, a rear surface portion 14, a front surface portion 15, and a curved portion 16.

  The left side surface portion 11 has end edges 21, 22, 23, 24, 25, and 26. The end edge 21 extends in the front-rear direction at a position spaced above the left end edge of the bottom surface portion 5 of the bottom cover 3. The edge 21 is shorter than the left edge of the bottom surface part 5 in the front-rear direction. The end edge 22 extends downward from the rear end of the end edge 21. The end edge 23 extends forward from the lower end of the end edge 22. The end edge 24 extends upward from the front end of the end edge 23. The edge 25 extends rearward from the upper end of the edge 24. The edge 26 extends upward from the rear end of the edge 25. The upper end of the end edge 26 is connected to the front end of the end edge 21.

  As shown in FIG. 3, the right side surface portion 12 has end edges 27, 28, 29, and 30. The end edge 27 extends in the front-rear direction at a position spaced above the right end edge of the bottom surface portion 5 of the bottom cover 3. The edge 27 has the same length as the right edge of the bottom surface portion 5 in the front-rear direction. The end edge 28 extends downward from the rear end of the end edge 27. The end edge 28 has the same length as the end edge 22 of the left side surface portion 11 in the vertical direction. The end edge 29 extends from the lower end of the end edge 28 to the front side. The end edge 30 extends upward from the front end of the end edge 29. The upper end of the end edge 30 is connected to the front end of the end edge 27.

  The upper surface portion 13 has the same dimension as the length of the edge 21 of the left side surface portion 11 in the front-rear direction. The upper surface portion 13 is constructed between the end edge 21 of the left side surface portion 11 and the end edge 27 of the right side surface portion 12.

  The rear surface portion 14 is constructed between the end edge 22 of the left side surface portion 11 and the end edge 28 of the right side surface portion 12.

  The front surface portion 15 has the same dimension as the length of the edge 24 of the left side surface portion 11 in the vertical direction. The front surface portion 15 is constructed between the end edge 24 of the left side surface portion 11 and the end edge 30 of the right side surface portion 12.

  The bending portion 16 is provided between the right end portion of the upper surface portion 13 and the right end portion of the front surface portion 15. The curved portion 16 is formed along a portion extending on the front side of the upper surface portion 13 in the end edge 27 of the right side surface portion 12 and a portion extending on the upper side of the front surface portion 15 in the end edge 30. Therefore, the left end edge 31 of the bending portion 16 extends from the upper surface portion 13 to the front side, curves in the middle, extends downward, and the lower end is connected to the front surface portion 15.

  Accordingly, the housing 2 has an opening 34 formed by the end edges 25 and 26 of the left side surface portion 11, the front end edge 32 of the upper surface portion 13, the upper end edge 33 of the front surface portion 15, and the left end edge 31 of the curved portion 16. ing.

  As shown in FIG. 5, the top cover 4 holds a lower chute 41 and an upper chute 42.

  The lower chute 41 is disposed in a space sandwiched between the bottom cover 3 and the top cover 4. As shown in FIGS. 8 and 9, the lower chute 41 includes a first wall surface 43, a second wall surface 44, a third wall surface 45, a fourth wall surface 46, and a fifth wall surface 47 as an example of a wall portion. Yes.

  8 and 9 is a direction in a state in which the lower chute 41 is attached to the image reading apparatus 1.

  As shown in FIGS. 7 and 8, the first wall surface 43 has a curved end edge 51, a rear end edge 52, and a lower end edge 53. The curved edge 51 is along the left edge 31 of the curved portion 16. The rear end edge 52 extends downward from the upper end of the curved end edge 51. The lower end edge 53 extends from the lower end of the curved end edge 51 to the rear side. Thereby, the 1st wall surface 43 is orthogonally crossed in the left-right direction. Further, the first wall surface 43 is exposed on the left side through a notch 35 formed by the edges 25 and 26 of the left side surface portion 11 of the top cover 4. The notch 35 is open in the left direction. The notch 35 is also open upward.

  As shown in FIG. 8, the second wall surface 44 extends in the left-right direction and is orthogonal to the front-rear direction. The second wall surface 44 is connected by the rear end edge 52 and the right end edge 54 of the first wall surface 43. Further, the second wall surface 44 is connected by the end edge 26 and the left end edge 55 of the left side surface portion 11.

  The third wall surface 45 extends in the left-right direction on the front side of the second wall surface 44 and is orthogonal to the up-down direction. The third wall surface 45 is connected to the lower end edge 53 and the right end edge 56 of the first wall surface 43. The third wall surface 45 is connected to the lower end edge 57 and the rear end edge 58 of the second wall surface 44.

  As shown in FIG. 9, the fourth wall surface 46 extends in the left-right direction on the rear side of the second wall surface 44 and is orthogonal to the up-down direction. The fourth wall surface 46 is continuous with the third wall surface 45 and is flush with the third wall surface 45.

  The fifth wall surface 47 extends in the left-right direction and is orthogonal to the front-rear direction. The fifth wall surface 47 is connected by the rear end edge 59 and the upper end edge 60 of the fourth wall surface 46.

  An actuator opening 61 is formed across the fourth wall surface 46 and the fifth wall surface 47 at the right end of the fourth wall surface 46 and the fifth wall surface 47.

  As shown in FIG. 8, the lower end portion of the second wall surface 44 is cut out except for the left side portion. Thus, the lower chute 41 is formed with an introduction port 71 surrounded by the first wall surface 43, the second wall surface 44 and the third wall surface 45. The introduction port 71 is open in the front-rear direction.

  The upper chute 42 is disposed on the rear side of the second wall surface 44 of the lower chute 41 as shown in FIG. The upper chute 42 extends in the left-right direction and extends in the front-rear direction.

  As shown in FIGS. 1 and 5, a discharge port 72 is formed in the rear surface portion 14 of the top cover 4. The discharge port 72 extends in the left-right direction at substantially the same position as the introduction port 71 in the vertical direction. The left end 72L of the discharge port 72 is at the same position as the left end 71L of the introduction port 71, as indicated by a virtual line in FIG. The right end 72 </ b> R of the discharge port 72 is located on the right side of the right end 71 </ b> R of the introduction port 71.

  A space extending in the front-rear direction along the upper chute 42 between the introduction port 71 and the discharge port 72 is a conveyance path 73 through which the sheet S introduced from the introduction port 71 is conveyed toward the discharge port 72.

<Internal mechanism>

  As shown in FIG. 5, the image reading apparatus 1 includes a sensor 81, a roller 82, a reading unit 83, and an urging unit 84 in a space sandwiched between the bottom cover 3 and the top cover 4.

  The sensor 81 is disposed below the lower chute 41. The sensor 81 includes a sensor main body 91 and an actuator 92. The actuator 92 extends upward from the sensor body 91. The tip of the actuator 92 protrudes above the fourth wall surface 46 of the lower chute 41 through the actuator opening 61 of the lower chute 41.

  When the sheet S is inserted into the introduction port 71, the leading edge of the sheet S presses the actuator 92 to the downstream side in the transport direction, and the actuator 92 tilts. When the actuator 92 tilts, the micro switch provided in the sensor main body 91 is switched from off to on. Thereby, it is detected that the sheet S is inserted into the introduction port 71.

  The roller 82 is disposed on the rear side of the upper chute 42. The roller 82 is attached to the rotating shaft 101. The rotating shaft 101 extends in the left-right direction as shown in FIGS. 10 and 11. The left end portion and the right end portion of the rotation shaft 101 are rotatably supported by support plates 102 and 103 erected on the bottom surface portion 5 of the bottom cover 3, respectively. The roller 82 is rotationally driven by the driving force of the motor 105. As shown in FIG. 4, the motor 105 is disposed on the bottom surface portion 5 between the left side surface portion 11 of the top cover 4 and the left support plate 102.

  As shown in FIG. 5, the reading unit 83 is disposed behind the fifth wall surface 47 of the lower chute 41 and below the roller 82. As shown in FIG. 12, the reading unit 83 includes a contact image sensor unit 111, a holder 112, and a transparent plate 113.

  Note that the directions indicated by arrows in FIGS. 12 and 13 are directions in a state where the reading unit 83 is attached to the image reading apparatus 1.

  The contact image sensor unit 111 extends in the left-right direction. The contact image sensor unit 111 includes an LED light source, a lens, an image sensor, and the like. Further, as shown in FIGS. 12 and 13, the contact image sensor unit 111 includes two protrusions 114 and 115, respectively.

  The two protrusions 114 are provided at the center in the front-rear direction of the left side surface 116 of the contact image sensor unit 111 with a space in the vertical direction. Each protrusion 114 extends from the left side surface 116 to the left side.

  The two protrusions 115 are provided at the center in the front-rear direction of the right side surface 117 of the contact image sensor unit 111 with a space in the vertical direction. Each protrusion 115 extends from the right side surface 117 to the right side.

  The holder 112 includes a front side plate 118 and a rear side plate 119.

  The front side plate 118 covers the front surface of the contact image sensor unit 111 and wraps around the front end portions of the left side surface 116 and the right side surface 117 of the contact image sensor unit 111. Further, the front side plate 118 includes a protruding portion 120. As shown in FIG. 12, the protruding portion 120 protrudes from the upper end portion of the front side plate 118 to the front side. The upper surface of the projecting portion 120 is formed on an inclined surface 121 that extends in the left-right direction and is inclined so that the front side is positioned on the lower side.

  The rear side plate 119 covers the front surface of the contact image sensor unit 111 and wraps around the front end portions of the left side surface 116 and the right side surface 117 of the contact image sensor unit 111.

  The transparent plate 113 is disposed on the upper side of the contact image sensor unit 111. The upper surface of the transparent plate 113 is a reading surface 122. The portion of the transparent plate 113 that is biased toward the rear side is in contact with a part of the circumferential surface of the roller 82 at the contact position CP1. The contact position CP1 is located behind the center of the transparent plate 113 in the front-rear direction.

  As shown in FIG. 7, the left restricting portion 131 includes a front wall 133 and a rear wall 134. The front wall 133 and the rear wall 134 extend in the up-down direction at the same position in the left-right direction with a space in the front-rear direction. The front wall 133 and the rear wall 134 sandwich the two protrusions 114 on the left side of the contact image sensor unit 111 in the front-rear direction.

  As shown in FIG. 6, the right restricting portion 132 includes a front wall 135 and a rear wall 136. The front wall 135 and the rear wall 136 extend in the up-down direction at the same position in the left-right direction with a space in the front-rear direction. The front wall 135 and the rear wall 136 sandwich the two protrusions 115 on the right side of the contact image sensor unit 111 in the front-rear direction.

  As a result, the reading unit 83 is restricted from moving in the front-rear direction while being movable in the up-down direction.

  As shown in FIG. 4, the urging portion 84 is located between the left restricting portion 131 and the right restricting portion 132 in the left-right direction. The biasing portion 84 includes a left coil spring 141 and a right coil spring 142. The left coil spring 141 and the right coil spring 142 are disposed at the same position in the front-rear direction with an interval in the left-right direction. The positions of the left coil spring 141 and the right coil spring 142 in the front-rear direction are substantially the same as the positions of the rollers 82 in the front-rear direction.

  One end of the left coil spring 141 is connected to a position biased to the rear side on the lower surface of the contact image sensor unit 111. The contact position CP2 between the upper end of the left coil spring 141 and the lower surface of the contact image sensor unit 111 is the same position in the front-rear direction as the contact position CP1 between a part of the peripheral surface of the roller 82 and the transparent plate 113. The other end of the left coil spring 141 is externally fitted to a left spring support portion 143 formed on the bottom surface portion 5 of the bottom cover 3. The lower end of the left coil spring 141 is in contact with the upper surface of the bottom surface portion 5.

  One end of the right coil spring 142 is connected to a position biased to the rear side on the lower surface of the contact image sensor unit 111. The contact position CP3 between the upper end of the right coil spring 142 and the lower surface of the contact image sensor unit 111 is the same position in the front-rear direction as the contact position CP1 between a part of the peripheral surface of the roller 82 and the transparent plate 113. The other end portion of the right coil spring 142 is externally fitted to a right spring support portion 144 formed on the bottom surface portion 5 of the bottom cover 3. The lower end of the right coil spring 142 is in contact with the upper surface of the bottom surface portion 5.

  The reading unit 83 is biased upward by the elastic force of the left coil spring 141 and the right coil spring 142. By this urging, a portion of the transparent plate 113 positioned above the left coil spring 141 and the right coil spring 142 is pressed against the peripheral surface of the roller 82 from below.

  The right coil spring 142 has a smaller diameter than the left coil spring 141 and a larger spring constant than the left coil spring 141. The natural length of the right coil spring 142 is the same as the natural length of the left coil spring 141. The lower end of the left coil spring 141 and the lower end of the right coil spring 142 are both in contact with the upper surface of the bottom surface portion 5 of the bottom cover 3. Thereby, the lower end of the right coil spring 142 is located at the same position in the vertical direction as the lower end of the left coil spring 141. Therefore, the elastic force of the right coil spring 142 is larger than the elastic force of the left coil spring 141. As a result, the right side of the transparent plate 113 is pressed more strongly against the peripheral surface of the roller 82 than the left side.

<Rotation restriction structure>

  The image reading apparatus 1 includes first extending portions 151 and 152 shown in FIG. 12 in the lower chute 41 in order to restrict the rotation of the reading portion 83 about an axis extending in the left-right direction. The image reading apparatus 1 includes second extending portions 153 and 154 shown in FIG. 9 in the lower chute 41 in order to restrict the rotation of the reading portion 83 around the axis extending in the left-right direction.

  As shown in FIG. 12, the first extending portion 151 is provided below the protruding portion 120 at the left end portion of the front plate 118 of the holder 112 of the reading unit 83. The first extending portion 151 extends from the front side plate 118 to the front side and extends in the left-right direction.

  The first extending portion 152 is provided below the projecting portion 120 at the right end portion of the front side plate 118 of the holder 112 of the reading unit 83. The first extending portion 152 extends from the front side plate 118 to the front side and extends in the left-right direction. The upper surface of the first extension 152 is disposed at the same position as the upper surface of the first extension 151 in the vertical direction. The right end of the first extension 152 is connected to an extension 155 provided on the front plate 118. The extension part 155 extends upward from the right end of the first extension part 152.

  As shown in FIG. 4, the second extending portion 153 is provided at the same position as the first extending portion 151 in the left-right direction. As illustrated in FIG. 9, the second extending portion 153 extends rearward from the fifth wall surface 47 of the lower chute 41. A lower end portion of the second extending portion 153 is located above the first extending portion 151 with a space between the first extending portion 151. The protruding part 120 is located above the first extending part 151 and the second extending part 153.

  The second extending part 154 extends rearward from the fifth wall surface 47 of the lower chute 41. The second extending portion 154 includes two walls 156 and 157. The walls 156 and 157 are provided at the right end of the lower chute 41. The walls 156 and 157 extend in the vertical direction with an interval in the horizontal direction. The lower end of the left wall 156 is disposed at the same position as the lower end of the second extending portion 153 in the vertical direction. The lower end of the right wall 157 is located below the lower end of the left wall 156. The walls 156 and 157 sandwich the extending portion 155 from the left and right sides.

<Scanning sheet image>

  When the image reading apparatus 1 is used, a terminal provided at one end of a communication cable (not shown) is inserted into the communication connector 8 through the insertion port 7. The other end of the communication cable is connected to a personal computer (not shown), for example.

  Then, as illustrated in FIG. 14A, one sheet S is inserted into the introduction port 71 from the third wall surface 45. At this time, the right edge of the sheet S is pressed against the first wall surface 43 with the first wall surface 43 as a reference.

  When the sheet S is inserted into the introduction port 71, the sensor 81 detects the sheet S. In response to the detection of the sheet S by the sensor 81, the motor 105 is driven. Due to the driving force of the motor 105, the roller 82 rotates counterclockwise when viewed from the right side.

  When the roller 82 rotates counterclockwise when viewed from the right side, a force is applied from the roller 82 to the transparent plate 113 in a direction in which the rear end portion of the reading unit 83 moves downward. By this force, a force that is rotated clockwise as viewed from the right side is applied to the reading unit 83. The two protrusions 114 are sandwiched by the left restricting portion 131 from both the left and right sides, and the two protrusions 115 are sandwiched by the right restricting portion 132 from both the left and right sides, thereby restricting the rotation of the reading unit 83. Further, due to tolerances, a gap is generated between the protrusion 114 and the front wall 133 and the rear wall 134 of the left restricting portion 131 and between the protrusion 115 and the front wall 135 and the rear wall 136 of the right restricting portion 132. Therefore, when the reading unit 83 rotates clockwise as viewed from the right side, as shown in FIG. 14B, the first extending portions 151 and 152 come into contact with the second extending portions 153 and 154 from the lower side, respectively. Accordingly, the force in the direction in which the rear end portion of the reading unit 83 moves downward is received by the second extending portions 153 and 154, and further rotation of the reading unit 83 is suppressed.

  When the user moves the sheet S to the rear side, the leading end portion of the sheet S introduced from the introduction port 71 is inserted between the peripheral surface of the roller 82 and the reading surface 122. When the upper surface of the sheet S comes into contact with the peripheral surface of the roller 82, a conveying force is applied from the roller 82 to the sheet S. With this conveying force, the sheet S is conveyed rearward and passes between the peripheral surface of the roller 82 and the reading surface 122. At this time, the sheet S on the reading surface 122 is irradiated with light from the LED light source of the contact image sensor unit 111. Then, when the reflected light from the sheet S is received by the image sensor of the contact image sensor unit 111, an image drawn on the lower surface of the sheet S is read. The read image data of the sheet S is sent to a personal computer via a communication cable connected to the communication connector 8.

  Thereafter, the rear end portion of the sheet S is separated from the peripheral surface of the roller 82, and the sheet S is discharged from the discharge port 72.

<Effect>

  As described above, a part of the circumferential surface of the roller 82 is in contact with the contact position CP1 biased to the rear side of the reading unit 83 of the reading surface 122. Therefore, when the roller 82 rotates, a force is applied from the roller 82 to the reading surface 122 in a direction in which the rear portion of the reading unit 83 moves downward. The first extending portions 151 and 152 extend from the reading unit 83 to the front side. The second extending portions 153 and 154 are located above the first extending portions 151 and 152. When a force is applied from the roller 82 to the reading surface 122, the first extending portions 151 and 152 come into contact with the second extending portions 153 and 154 from below, so that the force is applied to the second extending portions 153 and 154. It is accepted. Thereby, the rotation of the reading unit 83 due to the force applied from the roller 82 to the reading surface 122 can be suppressed. As a result, when the sheet S is inserted between the peripheral surface of the roller 82 and the reading surface 122 of the reading unit 83, the leading edge of the sheet S can be suppressed from being caught by the reading unit 83.

  Further, the image reading apparatus 1 includes an urging unit 84 configured to abut on the reading unit 83 from below and urge the reading unit 83 upward.

  According to this configuration, when the reading unit 83 is biased upward, the reading surface 122 can be brought into close contact with the sheet S conveyed between the peripheral surface of the roller 82 and the reading surface 122. Therefore, the reading unit 83 can read the image of the sheet S on the reading surface 122 satisfactorily.

  The contact position CP2 and the contact position CP3 between the lower surface of the contact image sensor unit 111 and the urging portion 84 are the same position in the front-rear direction as the contact position CP1 between a part of the circumferential surface of the roller 82 and the reading surface 122. .

  Thus, when a force is applied from the roller 82 to the reading surface 122 as the roller 82 rotates, a part of the force can be received by the urging unit 84. As a result, the rotation of the reading unit 83 due to the force applied from the roller 82 to the reading surface 122 can be further suppressed.

  The image reading apparatus 1 includes a protruding portion 120 provided in the reading portion 83, and the protruding portion 120 is positioned above the first extending portions 151, 152 and the second extending portions 153, 154 in the vertical direction, and reads Projecting from the front plate 118 of the portion 83 to the front side, the protruding portion 120 has an inclined surface 121 that is inclined upward toward the rear side.

  According to this configuration, the inclined surface 121 of the protrusion 120 can be used as a guide when the sheet S is disposed on the reading surface 122. Thereby, the sheet S can be smoothly arranged on the reading surface 122.

  Moreover, in the up-down direction, the inclined surface 121 is inclined so as to be positioned on the lower side toward the front side. Therefore, as compared with a configuration in which the upper surface of the protruding portion 120 is formed on a plane extending in parallel with the reading surface 122, the protrusion 120 is positioned below the lower chute 41 and the fourth wall surface 46 of the lower chute 41 in the vertical direction. The position can be brought close to the reading surface 122. Thereby, size reduction of the image reading apparatus 1 in an up-down direction can be achieved.

  The reading unit 83 includes an extending portion 155 that extends upward from the first extending portion 152. The fifth wall surface 47 of the lower chute 41 includes a wall 156 located on the left side of the extending part 155 and a wall 157 located on the right side of the extending part 155.

  Thereby, it can suppress that the reading part 83 moves to the left-right direction.

<Modification>

  As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.

  For example, as shown in FIG. 15A, a recess 201 may be formed in the front plate 118 instead of the first extension 151. In this case, the tip end portion of the second extending portion 202 extending rearward from the fifth wall surface 47 of the lower chute 41 is disposed in the recess 201.

  When the reading unit 83 rotates clockwise as viewed from the right side during the conveyance of the sheet S, as shown in FIG. 15B, the lower surface 203 of the concave portion 201 as an example of the first extending portion is moved to the second extending portion 202. Abut from below. Thereby, the force applied from the roller 82 to the reading surface 122 can be received by the second extending portion 202. Therefore, the rotation of the reading unit 83 can be suppressed.

  In addition, as shown in FIG. 16A, a recess 204 may be formed in the fifth wall surface 47 of the lower chute 41 instead of the second extending portion 153. In this case, the front end portion of the first extension portion 205 extending from the front side plate 118 to the front side is disposed in the recess 204.

  When the reading unit 83 rotates clockwise as viewed from the right side during conveyance of the sheet S, as shown in FIG. 16B, the first extended portion 205 becomes the upper surface 206 of the concave portion 204 as an example of the second extended portion. Abut from below. Thereby, the force applied from the roller 82 to the reading surface 122 can be received by the upper surface of the recess 204. Therefore, the rotation of the reading unit 83 can be suppressed.

  In addition, various design changes can be made to the above-described configuration within the scope of the matters described in the claims.

DESCRIPTION OF SYMBOLS 1 Image reading apparatus 2 Housing | casing 47 5th wall surface 82 Roller 83 Reading part 84 Energizing part 120 Protrusion part 121 Inclined surface 122 Reading surface 151 1st extension part 152 1st extension part 153 2nd extension part 154 2nd extension part 155 Extension part 156 Wall 157 Wall 202 Second extension part 203 Lower surface 205 First extension part 206 Upper surface CP1 Contact position CP2 Contact position CP3 Contact position S Sheet

Claims (5)

A reading unit having a reading surface and configured to read an image of a sheet positioned on the reading surface;
A roller in which a part of the peripheral surface comes into contact with a contact position that is biased to the downstream side in the sheet conveyance direction in the reading unit;
A first extending portion provided in the reading unit and extending upstream in the transport direction;
An image reading apparatus comprising: a second extending portion that is positioned on the roller side with respect to the first extending portion in a direction orthogonal to the reading surface and extends downstream in the transport direction. The first extending portion is located on the opposite side of the roller side with respect to the reading surface in the orthogonal direction,
The first extending portion is a protrusion protruding from the upstream end surface in the transport direction of the reading unit to the upstream side in the transport direction,
The second extending portion is located on the opposite side to the roller side with respect to the reading surface in the orthogonal direction,
2. The image reading apparatus according to claim 1, wherein the second extending portion is a protrusion protruding downstream in the transport direction from a wall portion located upstream of the reading portion of a housing that houses the reading portion. . An urging portion configured to abut against a portion of the reading portion opposite to the reading surface and to urge the reading portion toward the roller;
The image reading apparatus according to claim 2, wherein a contact position of the reading unit with the biasing unit is the same position as the contact position in the transport direction. A protrusion provided on the reading unit;
The protruding portion is located on the roller side with respect to the first extending portion and the second extending portion in the orthogonal direction,
The protruding portion protrudes upstream in the conveying direction with respect to an end surface on the upstream side in the conveying direction of the reading unit,
The image reading apparatus according to claim 2, wherein the protrusion has an inclined surface that is inclined so as to approach the reading surface toward a downstream side in the transport direction. The reading unit includes an extending part extending from the first extending part to the roller side in the orthogonal direction,
The housing includes two walls that are respectively positioned on one side and the other side in the rotation axis direction of the roller with respect to the extension portion, and extend to the opposite side to the roller side in the orthogonal direction. Item 5. The image reading apparatus according to any one of Items 2 to 4.

Images